The present invention relates to a method of loading a cassette and a cassette loading device for a cassette type magnetic recording and playback equipment and, more particularly, to a cassette loading device by which an unloading of a cassette may be carried out without fail even if the device is applied to a portable magnetic recording and playback equipment usable in any desired posture.
In FIG. 12, a conventional cassette loading device for front loading cassette type magnetic recording and playback equipment such as, for example, a video tape recorder (VTR) of a stationary type, that is, non-portable type is proposed which includes a device for loading a tape cassette K.
The tape cassette K is held at an initial position where the cassette projects a distance d outwardly from a front opening of the VTR. When the cassette K is manually inserted from the initial position, the cassette K reaches a position indicated by a dotted line in FIG. 12.
The loading device of FIG. 12 is constructed so that, as the cassette K is inserted from the initial position to the position indicated by the dotted line, the insertion (stroke) is performed against a elastic force of elastic means such as a spring, not shown. Therefore, when the cassette reaches the dotted line position; that is, the cassette reaches a stroke absorption condition, the elastic means is deformed to an energy stored condition. This elastic means will be referred to as a stroke absorption spring and a magnitude of the spring force of the stroke absorption spring determines the operational feeling at the time of insertion of the cassette.
Subsequently, when the cassette K reaches the dotted line position, a cassette position detecting means (not shown) detects the cassette position to actuate a motor (not shown). Thereafter, a driving mechanism composed of a gear train is operated by the output power of the motor so that the cassette K is moved horizontally rearwardly and is further moved in the vertical direction to reach a predetermined set position P. Then, the cassette position is detected by the cassette position detecting means, thereby stopping the motor.
When the loading operation of the tape cassette is thus finished, the operation mode will shift to a playback mode.
By manually pushing an eject button (not shown) the motor starts a reverse rotation, whereby the driving mechanism is operated in the opposite direction so that the cassette K is returned in a direction opposite to the direction of the arrows.
When the cassette K reaches the dotted line position, the cassette position detecting means detects the cassette position to thereby stop the motor. Subsequently, the aforesaid elastic means, held in the energy stored state in this position, causes the cassette K to be pressed outwardly by the distance d with its stored energy being released. Thus, all the components and members are returned back to the initial condition.
A cassette loading device of the aforementioned type is disclosed in, for example, Japanese Patent Unexamined Publication Nos. 12162/83 and 164051/83.
Since the conventional cassette loading device has been applied to the stationary type VTR, there is no serious problem in operation in accordance with the above-described operational principle. However, if such a cassette loading principle is applied to the portable type VTR, the loading device suffers from the following disadvantages.
As shown in FIG. 12, the stationary type VTR is used in the horizontal position however, a portable type VTR is not necessarily used in the horizontal position but rather the portable VTR may be held in a vertical position or suspended from an operator's shoulder to be held in the slant or oblique position.
More particularly, as shown in FIG. 13, there will be no problem in carrying out the loading of the tape cassette K in accordance with the method explained in conjunction with FIG. 12. However, a serious problem arises in the unloading operation of the tape cassette K. More specifically, the cassette K which has been returned from the set position back to the dotted line position by the power of the motor is to be pressed outwardly by the distance d to the solid line position solely by the spring force of the aforesaid elastic means with the motor being held in the stop condition. In this state, if the VTR is held in the vertical position, unlike the case where the VTR is held in the horizontal position, the tape cassette K must be pressed outwardly against a gravitational force of the cassette. Therefore, unless the elastic means meets this requirement, the tape cassette K will not be raised, and it is frequently difficult to unload the tape cassette K.
Of course, if the elastic force of the elastic means is increased, then the cassette K will readily be unloaded. However, in this case, when the cassette K is inserted for the loading, the cassette K must be depressed by the distance d against such an increased elastic force thereby adversely effecting the operational feeling of the cassette.
Accordingly, the aim underlying the invention resides in avoiding the above-noted disadvantages encountered in the prior art by providing a cassette loading device for a magnetic recording and playback equipment in which, even if the recording and playback equipment is held in a vertical position as well as in a horizontal direction, a tape cassette may be positively unloaded without any degradation of operational feeling.
According to advantageous features of the present invention, a cassette loading device is provided which comprises a driving means rotatable in normal and reverse directions, a driving mechanism for transmitting a power of the driving means to a cassette holder to transfer the cassette holder, and an elastic means mounted on the driving mechanism and for generating a elastic force against an inserting force when a tape cassette is inserted from an initial position to a cassette-in position. A position detecting means is provided for detecting the cassette holder reaching a predetermined position in its transfer path and for generating a signal, an initial position detecting means detects an initial position of the elastic means upon an initializing operation, and an eject signal generating means generates a signal for commanding an unloading of the cassette. A micro-processor controls the driving means in response to output signals of the position detecting means, the initial position detecting means and the eject signal generating means.
The tape cassette is inserted against the elastic force of the elastic means from the initial position to the cassette-in position. When the holder reaches the cassette-in position, the position detecting means feeds the signal to the micro-processor. The micro-processor causes the driving means to rotate in the normal direction, thus transferring the cassette holder to the cassette set position. By this normal rotation, the elastic force, stored by the insertion, of the elastic means is dissipated. When the cassette holder reaches the cassette set position, the position detecting means feeds the signal to the micro-processor. The micro-processor casues the driving means to be stopped, thereby completing the loading operation.
In response to the signal from the eject signal generating means, the micro-processor causes the driving means to rotate in a reverse direction, thus transferring the cassette holder to the initial position with the elastic force being stored in the elastic means, to thereby unload the tape cassette. When the cassette holder reaches the initial position, the position detecting means feeds the signal to the micro-processor. The micro-processor causes the driving means to rotate in the normal direction. At this time, the cassette holder is retained in the initial position by the elastic force of the elastic means. When the normal rotation causes the elastic means to reach its initial position, the initial position detecting means feeds the signal to the micro-processor which, in turn, stops the driving means to complete the unloading operation. Thus, the tape cassette is forcibly unloaded irrespective of the spring force of the spring means.